[x86] update test file with complete auto-generated check lines; NFC

Also, improve test names.

llvm/test/CodeGen/X86/float-conv-elim.ll

@@ -1,32 +1,33 @@
-; RUN: llc -mtriple=x86_64-unknown-linux-gnu -mcpu=x86-64 < %s | FileCheck %s
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=x86_64-- -mcpu=x86-64 < %s | FileCheck %s
 
-; Make sure the float conversion is folded away as it should be.
-; CHECK-LABEL: foo
-; CHECK-NOT: cvt
-; CHECK: movzbl
-define i32 @foo(i8 %a) #0 {
+define i32 @u8_f32_s32(i8 %a) {
+; CHECK-LABEL: u8_f32_s32:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    movzbl %dil, %eax
+; CHECK-NEXT:    retq
   %conv = uitofp i8 %a to float
   %conv1 = fptosi float %conv to i32
   ret i32 %conv1
 }
 
-; CHECK-LABEL: foo2
-; CHECK-NOT: cvt
-; CHECK: movsbl
-define i32 @foo2(i8 %a) #0 {
+define i32 @s8_f32_s32(i8 %a) {
+; CHECK-LABEL: s8_f32_s32:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    movsbl %dil, %eax
+; CHECK-NEXT:    retq
   %conv = sitofp i8 %a to float
   %conv1 = fptosi float %conv to i32
   ret i32 %conv1
 }
 
-; CHECK-LABEL: bar
-; CHECK-NOT: cvt
-; CHECK: movl
-define zeroext i8 @bar(i8 zeroext %a) #0 {
+define zeroext i8 @u8_f32_u8(i8 zeroext %a) {
+; CHECK-LABEL: u8_f32_u8:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    movl %edi, %eax
+; CHECK-NEXT:    # kill: def $al killed $al killed $eax
+; CHECK-NEXT:    retq
   %conv = uitofp i8 %a to float
   %conv1 = fptoui float %conv to i8
   ret i8 %conv1
 }
-
-attributes #0 = { nounwind ssp uwtable "less-precise-fpmad"="false" "frame-pointer"="all" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
-